Structural dependence of crystallization in glasses along the nepheline (NaAlSiO4) ‐ eucryptite (LiAlSiO4) join. Issue 7 (1st February 2018)

• Record Type: Journal Article
• Authors: Marcial, José; Kabel, Joey; Saleh, Muad; Washton, Nancy; Shaharyar, Yaqoot; Goel, Ashutosh; McCloy, John S.
• Is Part Of: Journal of the American Ceramic Society. Volume 101:Issue 7(2018)
• Page Start: 2840
• Page End: 2855
• Publication Date: 2018-02-01
• Subjects: aluminosilicates -- crystals/crystallization -- glass -- lithium oxide -- nuclear waste; Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.15439
• Languages: English
• ISSNs: 0002-7820

Abstract

Abstract: Lithium and sodium aluminosilicates are important glass‐forming systems for commercial glass‐ceramics, as well as being important model systems for ion transport in battery studies. In addition, uncontrolled crystallization of LiAlSiO4 (eucryptite) in high‐Li2 O compositions, analogous to the more well‐known problem of NaAlSiO4 (nepheline) crystallization, can cause concerns for long‐term chemical durability in nuclear waste glasses. To study the relationships between glass structure and crystallization, nine glasses were synthesized in the Li x Na1‐ x AlSiO4 series, from x = 0 to x = 1. Raman spectra, nuclear magnetic resonance (NMR) spectroscopy (Li‐7, Na‐23, Al‐27, Si‐29), and X‐ray diffraction were used to study the quenched and heat‐treated glasses. It was found that different LiAlSiO4 and NaAlSiO4 crystal phases crystallize from the glass depending on the Li/Na ratio. Raman and NMR spectra of quenched glasses suggest similar structures regardless of alkali substitution. Li‐7 and Na‐23 NMR spectra of the glass‐ceramics near the endmember compositions show evidence of several differentiable sites distinct from known Li x Na1‐ x AlSiO4 crystalline phases, suggesting that these measurements can reveal subtle chemical environment differences in mixed‐alkali systems, similar to what has been observed for zeolites.